/* ============================================================
   cover.css — 登录封面：混沌方舟
   布局参照赛托邦工作台登录页：左侧满版品牌画面 + 右侧深色登录面板。
   左侧画面由 js/ark-cover.js 实时渲染；不支持 WebGL 时显示下方 CSS/SVG 静态画面。
   只作用于 #login-view.cover，不影响登录后的工作台界面与飞书绑定页。
   ============================================================ */
#login-view.cover {
  /* 局部换成深色变量，表单控件沿用 components.css 的既有样式 */
  --bg-page: #07080A;
  --surface: #16171B;
  --fill: rgba(255, 255, 255, .07);
  --fill-hover: rgba(255, 255, 255, .11);
  --sep: rgba(255, 255, 255, .08);
  --sep-strong: rgba(255, 255, 255, .14);
  --text-1: #F1EDE4;
  --text-2: #A19D96;
  --text-3: #66635F;
  --accent: #FF7A6B;
  --accent-hover: #FF968A;
  --accent-soft: rgba(255, 90, 72, .14);
  --danger: #FF6B5B;
  --btn-primary-bg: #F1EDE4;
  --btn-primary-text: #111214;
  --focus-ring: 0 0 0 3px rgba(226, 52, 38, .55);
  --ark-red: #E23426;
  color-scheme: dark;
  color: var(--text-1);
  background: var(--bg-page);

  display: grid;
  grid-template-columns: minmax(0, 1.42fr) minmax(420px, 1fr);
  align-items: stretch; justify-content: stretch;
  min-height: 100vh; min-height: 100dvh;
  padding: 0;
}

/* ---------- 左：画面 ---------- */
.cover-stage {
  position: relative; overflow: hidden;
  min-height: 100vh; min-height: 100dvh;
  background: #050608;
  isolation: isolate;
}
.cover-stage canvas {
  position: absolute; inset: 0; width: 100%; height: 100%;
  display: block; opacity: 0;
  transition: opacity 1.2s ease;
}
.cover-stage.cover-live canvas { opacity: 1; }
.cover-stage[data-cover-mode="fallback"] canvas { display: none; }

/* 静态画面：WebGL 就绪前垫底；降级时作为最终画面 */
.cover-fallback {
  position: absolute; inset: 0;
  background:
    radial-gradient(60% 38% at 34% 30%, rgba(196, 210, 236, .30), transparent 70%),
    radial-gradient(120% 30% at 50% 63%, rgba(120, 20, 10, .42), transparent 70%),
    linear-gradient(180deg, #0B0D12 0%, #15171D 46%, #2A1210 61%, #07090B 63%, #040506 100%);
}
.cover-stage::after { /* 右缘过渡，衔接登录面板 */
  content: ''; position: absolute; inset: 0 0 0 auto; width: 22%;
  background: linear-gradient(90deg, rgba(7, 8, 10, 0), rgba(7, 8, 10, .85));
  pointer-events: none; z-index: 1;
}

/* 标题底衬：静态的暗色晕染，保证文字与背后海面的对比稳定 */
.cover-title::before {
  content: ""; position: absolute; z-index: -1; left: -90px; right: -120px; top: -70px; bottom: -60px;
  background: radial-gradient(closest-side, rgba(5, 6, 8, .62), rgba(5, 6, 8, .38) 55%, rgba(5, 6, 8, 0));
  pointer-events: none;
}
.cover-title {
  position: absolute; left: clamp(28px, 5vw, 72px); bottom: clamp(32px, 7vh, 80px);
  z-index: 2; max-width: 70%;
  text-shadow: 0 2px 24px rgba(0, 0, 0, .55);
  pointer-events: none;
}
.cover-eyebrow {
  display: flex; align-items: center; gap: 10px;
  font-size: 12px; letter-spacing: .32em; color: rgba(241, 237, 228, .72);
  font-weight: 600; text-transform: uppercase;
}
.cover-eyebrow::before { content: ''; width: 28px; height: 2px; background: var(--ark-red); }
.cover-title h2 {
  margin-top: 14px;
  font-size: clamp(44px, 5.6vw, 84px); line-height: 1.02; font-weight: 800;
  letter-spacing: .06em; color: #F4F0E8;
}
.cover-title .cover-tag { margin-top: 12px; font-size: clamp(15px, 1.3vw, 18px); color: rgba(241, 237, 228, .78); letter-spacing: .08em; }

.cover-motion {
  position: absolute; right: 16px; bottom: 16px; z-index: 3;
  padding: 6px 12px; border-radius: 999px;
  font: 500 12px/1.4 var(--font); letter-spacing: .04em;
  color: rgba(241, 237, 228, .78);
  background: rgba(10, 11, 14, .45);
  border: .5px solid rgba(255, 255, 255, .16);
  -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px);
  cursor: pointer;
}
.cover-motion:hover { color: #FFF; background: rgba(10, 11, 14, .65); }
.cover-motion:focus-visible { outline: none; box-shadow: var(--focus-ring); }
.cover-stage[data-cover-mode="fallback"] .cover-motion,
.cover-stage[data-cover-mode="init"] .cover-motion { display: none; }

/* ---------- 右：登录面板 ---------- */
.cover-panel {
  position: relative; display: flex; align-items: center; justify-content: center;
  padding: 40px clamp(24px, 4vw, 64px);
  background:
    radial-gradient(80% 50% at 100% 0%, rgba(226, 52, 38, .07), transparent 60%),
    radial-gradient(70% 60% at 0% 100%, rgba(120, 140, 180, .06), transparent 60%),
    #07080A;
}
#login-view.cover .login-card {
  width: 100%; max-width: 380px;
  padding: 36px 32px 26px;
  background: rgba(20, 21, 25, .66);
  border: .5px solid rgba(255, 255, 255, .09);
  border-radius: 20px;
  box-shadow: 0 1px 0 rgba(255, 255, 255, .05) inset, 0 30px 80px rgba(0, 0, 0, .5);
  -webkit-backdrop-filter: blur(18px); backdrop-filter: blur(18px);
}
#login-view.cover .login-brand { text-align: left; margin-bottom: 26px; }
#login-view.cover .login-brand .brand-logo {
  width: 132px; margin: 0 0 18px;
  filter: invert(1) contrast(1.5); mix-blend-mode: screen !important;
  background: transparent !important; padding: 0 !important; border-radius: 0 !important;
}
#login-view.cover .login-card h1 { font-size: 24px; letter-spacing: .01em; }
#login-view.cover .login-sub { font-size: 13px; }
#login-view.cover .field select { appearance: auto; }
#login-view.cover .btn-primary { letter-spacing: .12em; }
#login-view.cover .login-oauth a.btn { background: transparent; color: var(--text-1); border: .5px solid var(--sep-strong); }
#login-view.cover .login-oauth a.btn:hover { background: var(--fill); }
#login-view.cover .hint a { color: var(--text-2); }
#login-view.cover .hint a:hover { color: var(--text-1); }
#login-view.cover .login-card::before { /* 卡片顶边一道品牌红 */
  content: ''; display: block; width: 36px; height: 3px; margin: -12px 0 22px;
  background: var(--ark-red); border-radius: 2px;
}

/* ---------- 中等宽度：画面变窄 ---------- */
@media (max-width: 1100px) {
  #login-view.cover { grid-template-columns: minmax(0, 1fr) minmax(400px, 1fr); }
  .cover-title h2 { font-size: clamp(40px, 5vw, 60px); }
}

/* ---------- 手机/竖屏：上画面、下表单 ---------- */
@media (max-width: 860px) {
  #login-view.cover { display: block; padding: 0; }
  .cover-stage { min-height: 0; height: 46vh; height: 46svh; }
  .cover-stage::after {
    inset: auto 0 0 0; width: auto; height: 40%;
    background: linear-gradient(180deg, rgba(7, 8, 10, 0), rgba(7, 8, 10, .92));
  }
  .cover-title { left: 20px; bottom: 34px; max-width: calc(100% - 40px); }
  .cover-eyebrow { font-size: 10px; letter-spacing: .26em; }
  .cover-title h2 { font-size: 40px; margin-top: 10px; }
  .cover-title .cover-tag { font-size: 14px; margin-top: 6px; }
  .cover-motion { top: calc(env(safe-area-inset-top) + 12px); bottom: auto; right: 12px; }
  .cover-panel { display: block; padding: 0 16px calc(env(safe-area-inset-bottom) + 24px); background: #07080A; }
  #login-view.cover .login-card {
    position: relative; margin: -18px auto 0; max-width: 480px;
    padding: 24px 20px 16px;
  }
  #login-view.cover .login-brand { display: flex; align-items: center; gap: 12px; margin-bottom: 18px; }
  #login-view.cover .login-brand .brand-logo { width: 92px; margin: 0; }
  #login-view.cover .login-brand h1 { font-size: 20px; }
  #login-view.cover .login-brand .login-sub { display: none; }
  #login-view.cover .login-card::before { margin: -6px 0 16px; order: -3; }
  /* 基础样式在手机上把飞书登录提升为实心主按钮，这里保持一致 */
  #login-view.cover .login-oauth a.btn { background: var(--btn-primary-bg); color: var(--btn-primary-text); border: none; }
}

@media (prefers-reduced-motion: reduce) {
  .cover-stage canvas { transition: none; }
}